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  1. Hi, I'm converting my Blu-ray collection to digital and in the process of trying to shrink these 30GB movies down to 4GB or less I keep getting particles outlining the people in the movies. I have my settings set at MKV, X265 10bit, with constant quality set to 22, speed set to slow, and constant frame rate.

    I've used HandBreak, Vid Coder, MyFFmpeg, etc.

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    [Attachment 83415 - Click to enlarge]
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  2. This screenshot really shows how bad it is.
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    [Attachment 83419 - Click to enlarge]
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  3. Compression and re-encoding artifacts. One cannot expect same quality by shrinking the filesize by a factor of 1/8. You need to find your sweet spot between encoder, filesize (bitrate), frame resolution, noise filtering etc.
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  4. Captures & Restoration lollo's Avatar
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    Buy a larger drive and leave the video as they are
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  5. That's a too big for streaming.
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  6. Originally Posted by Sharc View Post
    Compression and re-encoding artifacts. One cannot expect same quality by shrinking the filesize by a factor of 1/8. You need to find your sweet spot between encoder, filesize (bitrate), frame resolution, noise filtering etc.
    I tried everything I can think of, and the file size is always over what I want it to be.
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    Originally Posted by Marbule_Brea View Post
    Originally Posted by Sharc View Post
    Compression and re-encoding artifacts. One cannot expect same quality by shrinking the filesize by a factor of 1/8. You need to find your sweet spot between encoder, filesize (bitrate), frame resolution, noise filtering etc.
    I tried everything I can think of, and the file size is always over what I want it to be.
    Use 2-pass VBR and set the bit rate explicitly
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  8. The source has a lot of film grain. A lot of the compression of high compression codecs comes from not repeating parts of the picture that don't change from frame to frame. Film grain changes with every frame so it doesn't compress well. What you want to do is filter away the grain before compression.

    Another thing you can do is reduce the resolution. Fewer pixels requires less bitrate. But you loose a little detail too.

    It's all a matter of where you want to make your compromises.
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  9. Originally Posted by jagabo View Post
    The source has a lot of film grain. A lot of the compression of high compression codecs comes from not repeating parts of the picture that don't change from frame to frame. Film grain changes with every frame so it doesn't compress well. What you want to do is filter away the grain before compression.

    Another thing you can do is reduce the resolution. Fewer pixels requires less bitrate. But you loose a little detail too.

    It's all a matter of where you want to make your compromises.
    Ah, that makes a lot of sense. I did notice that this film had a lot more film grain than the other films I converted which were about the same size after being ripped but I was able to get them down to the size I wanted while keeping great quality. I'll make those changes right away!
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  10. Originally Posted by davexnet View Post
    Originally Posted by Marbule_Brea View Post
    Originally Posted by Sharc View Post
    Compression and re-encoding artifacts. One cannot expect same quality by shrinking the filesize by a factor of 1/8. You need to find your sweet spot between encoder, filesize (bitrate), frame resolution, noise filtering etc.
    I tried everything I can think of, and the file size is always over what I want it to be.
    Use 2-pass VBR and set the bit rate explicitly
    This helped a lot!
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  11. With constant quality encoding the encoder uses whatever bitrate is required to achieve the specified quality. You don't know what bitrate that will be beforehand. If you need a specific file size you want to use bitrate based encoding. Bitrate is defined as:
    Code:
    bitrate = stream size / running time
    The full file size is the sum of the sizes of all streams (audio, video, subs...) and a little overhead for container organization. But the size of the video stream usually far outweighs all the other data so for a rough computation you can use the file size and running time to determine what bitrate to use:
    Code:
    bitrate = file size / running time
    So if you have a 2 hour video and you want a 4 GB file:
    Code:
    bitrate = file size / running time
    bitrate = 4,000,000,000 bytes * 8 (bits per byte) / 7200 seconds
    bitrate = 32,000,000,000 bits / 7200 seconds
    bitrate = 4,444,444 bits per second
    birate ~= 4,444 kbit/sec
    If you need more accurate file sizes there are bitrate calculators that let you specify the sizes or bitrate of all the other streams.
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  12. Originally Posted by jagabo View Post
    With constant quality encoding the encoder uses whatever bitrate is required to achieve the specified quality. You don't know what bitrate that will be beforehand. If you need a specific file size you want to use bitrate based encoding. Bitrate is defined as:
    Code:
    bitrate = stream size / running time
    The full file size is the sum of the sizes of all streams (audio, video, subs...) and a little overhead for container organization. But the size of the video stream usually far outweighs all the other data so for a rough computation you can use the file size and running time to determine what bitrate to use:
    Code:
    bitrate = file size / running time
    So if you have a 2 hour video and you want a 4 GB file:
    Code:
    bitrate = file size / running time
    bitrate = 4,000,000,000 bytes * 8 (bits per byte) / 7200 seconds
    bitrate = 32,000,000,000 bits / 7200 seconds
    bitrate = 4,444,444 bits per second
    birate ~= 4,444 kbit/sec
    If you need more accurate file sizes there are bitrate calculators that let you specify the sizes or bitrate of all the other streams.
    Thanks for this.
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  13. Originally Posted by jagabo View Post
    The source has a lot of film grain. A lot of the compression of high compression codecs comes from not repeating parts of the picture that don't change from frame to frame. Film grain changes with every frame so it doesn't compress well. What you want to do is filter away the grain before compression.

    Another thing you can do is reduce the resolution. Fewer pixels requires less bitrate. But you loose a little detail too.

    It's all a matter of where you want to make your compromises.
    What setting do I pick to remove the grain?

    Image
    [Attachment 83508 - Click to enlarge]

    Image
    [Attachment 83507 - Click to enlarge]
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